Refillable-fuse cartridge.



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H. LUTZ.

REFLLALE FUSE CARTRIDGE. APPUcATxon man APR.23,\918.

mmm 0015.221918.

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KNVENTOR UNITED STATES PATENT GFFICE.

HERBERT LUTZ, F-IAMILTON, ONTARIO, CANADA, ASSIGNOR 0F ONE-HALF TO GEORGE MORRIS, 0F HAMILTC'N, ONTARIO, CANADA.

REFILLABLE-FUSE CARTRIDGE.

Specification of Letters Patent.

' Patented Uot. 22, 1918.

Application filed April 23. 1918. Serial NoA 230,307.

vented a new and Improved Relillable-Fuse Cartridge, of which the following is a specification.

This invention has reference to certain improvements in inc losed or cartridge fuses of the re'lillable type involving the use `ot a casing of insulated material and wherein the fusible element is removably contained so that the said element may he readily replaced for a new fuse, Whenever it is blown.

Primarily, my invention seeks to provide a fuse cartridge of the character stated, of a simple and inexpensive construction, in which the parts are especially designed to provide a quick rellabl@ fuse` having contacts at the outer or cap ends of the casing designed ior keeping the contacts cool and presenting a longifuse space.

- My invention in its complete make-up embodies an improved construction oi casing end caps, the knife contacts and the engaging ends oi' the iuse element whereby a quick, convenient and effective interlocking of the parts may be obtained and the said parts arranged to produce a compact car tridve in which the )ossibilit` of the lusine4 C) i D element and the interlocking end connections becoming disengaged or out of proper operative electrical contact is reduced to the niinimuin.

My invention also embodies certain details olf construction and combination of parts, all of which will hereinafter be fully explained, specilically pointed out in the appended claims and illustrated in the accompanying drawings, in which: f

Figure l is a perspective vieW of my imu proved quick relillahle fuse cartridge.

Fig. 2 is a longitudinal section thereof, thel'iarts being at their operatively connected position. y

Figs. 3 and are cross sections thereof taken on the line 3--3 and 411-4 respectively on Fig. 2.

Fig. 5 is a perspective view of one of the knife contacts and an adjacent. end of the.

casing to which vthe contact is connected, when the, parts .are assembled.

Fig. t3 is a detail diagrammatic longitudinal section of one end of the cartridge casing` the knife contact and the cap that join with the said casing end, the several parts being.positioned to indicatev the manner in which the adjacent fuse end may be interiocliably connected therewith.

Fig. 7 is a detail longitudinal section of one end oi a casing and a modified construcf tion of a small knife blade contact and the coperating casing cap. l

Fig. 8 is a perspective view of the said inodilied form oi Contact.

Fig. 9 is a detail vievv of a modified form ot the fuse element hereinafter referred to.

Fig. l0 is a detail View oli' the fuse strip.

ln carrying out my invention, I provide a cartridge body in the nature of an open ended tube or casing l, of suitable insulating material, provided along its length With a mica covered sight opening l@ for-inspecting the fuse. i Y

In shaping up the tubular casing 1, each end thereof has a sector section cut out to thereby form longitudinal extensions ll-ll, each having a'slot-vvay l2 Whose inner ends merge with oppositely disposed lateral depressionsor notches 13'13 that constitute parts of the interlocking elements presently more fully described.

The fuse elementinmy construction oi' fuse cartridge mayconsist of a thin metal strip 2, as shown, or it may be formed of wire as-shovvn in Fig. 9, and the said element extends diagonally across the fuse chamber to thereby present a long iuse space.

The ends ot the fuse' 2, when formed of a metal strip, each have an aperture 20, but

when the4 fuse is formed ot' vvire, the said fuse ends terminate in eye loop's, the said apertures 20 or eye loops being provided for engaging' with the fuse fastening 4screws 6 6, presently again referred to.

yBy referring more particularly to Fig. 2 ot the drawings, it Will be noticed that, When the parts are assembled `lor use, theends ot' the fuse extend through long slots or openings l2 in the casing extensions l1l and engage With the knife blade contacts 3, of which there is one for each end of the casing.

The knife blade contacts 3, one of Which is shown in detail in Fig. 5, each include a member 30 that constitutes an end extension that projects from the longitudinal axis of the casing l and is provided with the usual lateral recess 30a for supporting the cartridge in the usualoperative position.

The knife blade conta ct 3 also includes an fio angled nien'iber 31 adapted for seating in the end grooves 12"-12"1 of the casing and a fuse contacting member 34.

Contact member 34 has a beveled notch 3 la in its end and the notches 34 of the members 34, when the parts are assembled, oppose undercut beveled notches 14-14 in the ends of the casing 1, as is clearly shown in Figs. 2 and G of the drawings, and for the reason presently explained.

The contact members 34 of the blades 3 are of sutlicient width to seat upon the opposing bearing edges 12 of the casing extensions 11-11 and the said members each have inwardly bent flanges or lugs 35-35 forinterlockably engaging with the notches 13 in the casing extensions, when the parts are assembled as in Figs. 1 and 2.

4-t designate cup-shaped caps that lit over and form end closures for the tubular casing 1 and each of said caps 4, when the contacts 3 are of the form shown in Figs. 1, 2, 3 and 5, have slots 40 for slipping Yover the bracket-like extensions 30 of the said contacts. lllhen, however, the contacts are adapted for use on small fuses, the said contacts are shapedwvithout the bracket extensions 30, as shown in Figs. 8 and 9, and when the contacts are thus shaped, the slots in thel caps 4, are omitted, but in either of the forms stated, the said caps 4 have one or more vent apertures 44. as shown.

The fuse contacting face of each knife blade 3 has a threaded aperture 36 for receiving the clamp screws 6 that pass through the apertures in the caps 4 and the apertures .or eyes 36 in the-fuse strip or wire.

8-8 designate the screws that secure the caps to the casing end.

From the foregoing description taken in connection with the drawings, the complete construction and the advantages of my improved t'use cartridge will be readily apparent to those skilled in the art to which my invention relates.

It is to be noted that by forming the ends of the casing, the blade contacts, the end caps, and securing the latter by screws 8-8,

as described and shown, when a fuse is dis-l rupted by overload or overheating by simply removing the screws 8 8, the caps with theirrespective blade contacts, the attached fuse portions may be readily pulled out from the casing end and the fuse portions pulled from their contacts 3 and the caps 4 .by removing the clamp screws 6.

To relill the cartridge, a new fuse strip or wire is attached to one of the caps 4 and stated, the end of the fuse is bent down be- 'tween the notch 34 and onto the contact bearing 34, after which the cap 4 is slipped over the casing extension 11, the member 34 and the said fuse end, the latter and the member 34 being interlocked by applying the screw 6 which clamps the fuse end between the contact 34 and the ca as is clearly shown in Figs. 2 and 3. ap 4 is then made secure on the casing 1 by applying the screw 8.

fWhat I claim is: I

1. In a rellablefuse cartridge, a tubular casinghaving end extensions, each of the said extensions rbeing longitudinally slotted, a contact member for each extension, the said extensions 'and the contact members having interlocking portions, acap plate insertible over each casin extension and the contact member, a fusi le element having its end extended between the caps and their respective' contact member, means for clamping said caps and their respective contact members and the'fusible element-ends, and other means for securing the caps onto the casing.

2. In a vreiillable fuse cartridge, an insulated vcasing open at both'ends and having each end formed with, an extension longitudinally slotted, the two extensions bein reversibly arranged whereby the opening in the, said extensions face in diametrically opposite directions, a contact member for each extension, the latter and their respective cont-act members having interlocking portions, a diagonally projected fuse element having its end projected' for engaging the opposite. end contacts, end caps that form the closures for the casing ends, means for clamping the ends of the fusible elements between the contacts and the caps and other means for securing the caps over the casing end.

3. A- refillable fuse. cartridge comprising a tubular shell of an insulating material rand having longitudinally slotted end extensions, the said end extensions having bearing faces parallelwith their slots and oppositely disposed vertical guide ways in their outer ends, the extensions being reversibly arranged whereby their slot-ways will be projected in diametrically` opposite directions, a knife blade Contact for each end extension of the shell said blade contacts each including a mein er for seating'on the bearings of the slotted shell end extensions, an angled portion Whose opposite. ends are. adapted for sli'dably engaging the vertical 'guide ways 'in the said extensions and a braeket portion that extends outwardly from theshell in the longitudinal axis thereof, a cross over fuse vmember Whose endsl are extended to rest on the blade cnntact members7 a vcap member for each endjof the tubular shell, the said cap'members each having a` central slot for the bracket extensions of the blade contacts at their respective ends, means forv clamping the said ends of the fuse members between the knife blade contacts 'and the caps, and otlieil means for securing the caps to close. over the open endsof the shell.

Ll. reillable fuse cartridge that comprises the following elements in eombination5 a tubular shell of insulating material formed with end extensions, the said ex# tensions being longitudinally slotted Wlieie by oppnsite side bearingsaregfo'rrned on saidextensions, the two extensieiis'fbeing pro.-

jeeted dlametrically oppositeeaeh other, the

bearings-0n each extensionv havin transu 'versely alined notches at ytlieirinner ends,v

the open ends of the extension being formed with oppositely disposed Vertical guides, a

knife blade Contact foreach end extension,

said Contact each' including a bearing portion for seating on the side bearings of their relatively respective extensions,- each of the said portions having inturned -members for interlocking with the sockets in their re` .spective eXt'e11s1ons,'sa1d knife blade con-A ta'e'ts also including Vangled portions for slide-bly engaging the vertical guides 'n the end `,eXtensions,y a cross over -fnse member` Whose vends are extended for resting on the blade Contact member, a cap member for eaeliend of the tubular shell, -nieans for :clamping the said ends of the fnseniember between the knife blade contacts and the Caps, the adjacent ends of the tubular shell -and the'knife blade contacts having'opposing beveled notches, and means for vsecuring thevcaps to close over the open ends of 

